National Accessibility Evaluation Pooled-Fund Study

The National Accessibility Evaluation (NAE) provides nationwide access data by mode (auto, transit, and bike) at the census block level. Produced by the University of Minnesota’s Accessibility Observatory, the NAE is in the second phase of a national pooled-fund study. Phase 2 will continue to provide data about access to jobs and include new measures such as access to educational and health care facilities. The study is funded through the Transportation Pooled Fund Program, a part of the National Cooperative Highway Research Program. The Minnesota Department of Transportation serves as the lead agency.

Phase 1 of the NAE (2014–2019), established a new national data source for multimodal job access and documented access trends by different travel modes. The Access Across America series of annual reports tracks these trends for the nation’s 50 largest metropolitan areas. The work captures a range of issues—from the impact of congestion on auto-oriented metros to documenting how investments in transit or bike infrastructure broaden commuter choices.

Phase 2 of the NAE (2020-2024) will continue to provide annual updates of national job access data and expand destination types to include educational and health care facilities.

The Accessibility Observatory team works with study partners to integrate access data and concepts into transportation planning, scenario evaluation, and performance management. Pooled-fund partners and other collaborators also provide input into additional research questions and ways to expand the use of access measures.

Benefits of Access Metrics

Transportation projects are undertaken to provide connectivity—the ability for people or things to physically travel—between locations or to lower travel times where connectivity already exists. As long-term infrastructure investments, transportation systems are not built to satisfy individual trips at specific times, but rather to provide capacity that can be used to satisfy a huge variety of potential trips over the system’s lifetime. This potential for interaction can be regarded as the fundamental product of transportation systems. 

Accessibility metrics directly reflect this potential by combining network travel times with the locations and value of the many origins and destinations served by a multimodal transportation system. Accessibility combines the simpler concept of mobility with an understanding that travel is driven by a desire to reach destinations.